This invention relates generally to drafting tables and, more particularly, is directed to a rotatable drafting table.
Conventionally, draftsman use stationary drafting tables to construct drawings. These tables are usually adjustable in height and can be swivelled to vary the angle or pitch of the table. In addition, it is known to provide parallel slides above the drafting surface of such tables. Generally, such parallel slides ride along a wire secured around the drafting table so as to move up and down therewith for aiding the draftsman in drawing straight and parallel lines.
However, one disadvantage associated with such conventional drafting tables is that the paper on which the drawing is made is constantly being shifted on the drafting table by the draftsman. Thus, the paper may initially be secured to the drafting table by pins and the like to prevent movement of the paper when drawing thereon. However, to move such paper, the pins must be removed, the paper moved to a different location on the drafting table and then the pins reinserted. This is cumbersome and time consuming.
Accordingly, rotatable drafting tables have been proposed, for example, as disclosed in U.S. Pat. Nos. 2,713,723 and 3,345,751. In both of these tables, a circular drafting board is rotatably mounted in a base board such that the upper surfaces of the drafting board and base board are coplanar with each other. Further, a parallel slide is mounted to the base board above the circular drawing board for slideable movement thereacross.
A problem with such drafting tables, however, is that the drafting area is reduced. Specifically, because the drafting board is formed in a circular configuration, the effective drafting area, as opposed to a conventional rectangular drafting board, is small. If the circle is increased in size, then the base board which rotatably supports the circular drafting board, must consequently be increased in size, which results in additional space being occupied.
Further, with a circular drafting board, the paper must generally be situated near the center of the circle to obtain maximum usage thereof. This results in the paper being positioned further away from the draftsman than with a conventional rectangular drafting board where the paper can be positioned at the edge of the drafting board. As a result, the draftsman must reach out further, making it more difficult for the draftsman to draw on the paper. See also U.S. Pat. Nos. 324,855; 915,418; 1,395,200; 3,261,099; and 4,450,774 for similar disclosures. As to U.S. Pat. No. 1,395,200, there is disclosed therein a brake spring 20 and screw 19 for locking the rotatable drafting board in position. U.S. Pat. No. 2,610,099 discloses a rotating and reciprocating table top. However, this table top is not used as a drafting table, but rather, is used as a support for a television receiver. Thus, the problem of constructing a parallel slide with a rectangular drafting board is not disclosed or suggested by this patent.